title: Simvastatin ameliorates liver fibrosis via mediating nitric oxide synthase in rats with non-alcoholic steatohepatitis-related liver fibrosis.
abstract: BACKGROUND
  Simvastatin exerts pleiotropic effects on cardiovascular system. However, its effect on non-alcoholic fatty liver disease, especially the liver fibrosis, remains obscure. We aimed to clarify the relationship between simvastatin and liver fibrosis both in vivo and in vitro.
  
  
  METHODS
  A High-fat diet was given to establish rat models with non-alcoholic steatohepatitis (NASH)-related liver fibrosis and simvastatin (4mg·kg(-1)·d(-1)) was administrated intragastrically until hepatic histological findings confirmed the appearance of fibrosis. Human hepatic stellate cell (HSC) line lx-2 cells were cultured in an adipogenic differentiating mixture (ADM) and then were treated with transforming growth factorβ1 (TGF-β1), served as a positive control, simvastatin, TGF-β1 plus simvastatin, Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME, a inhibitor of nitric oxide synthase), and L-NAME plus simvastatin, respectively. The expressions of endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), and Collagen І as well as cellular α-smooth muscle actin (α-SMA) were measured by real-time reverse transcriptase-polymerase chain reaction (qRT-PCR) and Western blot in liver tissue and HSC.
  
  
  RESULTS
  With the progress of NASH-related fibrosis, hepatic mRNA and protein expressions of iNOS, α-SMA, and Collagen І were increased while those of eNOS were decreased. Compared with model rats in 24(th) week group, rats in simvastatin group had less expressions of iNOS, α-SMA, and Collagen І and more expressions of eNOS. In vitro, LX-2 cells acquired quiescent phenotype when cultured in ADM, and TGF-β1 could activate the quiescent HSC. Simvastatin inhibited LX-2 cells activation due to TGF-β1 or L-NAME by increasing the expression of eNOS and decreasing the expression of iNOS.
  
  
  CONCLUSIONS
  Simvastatin improves the prognosis of NASH-related fibrosis by increasing the expression of eNOS, decreasing the expression of iNOS, and inhibiting the activation of HSC.
authors.affiliation: Department of Infectious Diseases, the Third Affiliated Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Caiyan
authors.initials: C
authors.lastname: Zhao
authors.forename: Junying
authors.initials: J
authors.lastname: Zhou
authors.forename: Zhen
authors.initials: Z
authors.lastname: Zhen
authors.forename: Yadong
authors.initials: Y
authors.lastname: Wang
authors.forename: Chuan
authors.initials: C
authors.lastname: Shen
mesh_terms: D000199:Actins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D000818:Animals; D002478:Cells, Cultured; D024042:Collagen Type I / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D059305:Diet, High-Fat / Q000009:adverse effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005234:Fatty Liver / Q000188:drug therapy* / Q000201:enzymology / Q000209:etiology / Q000473:pathology; D015870:Gene Expression / Q000187:drug effects; D055166:Hepatic Stellate Cells / Q000187:drug effects / Q000201:enzymology / Q000473:pathology; D006801:Humans; D000960:Hypolipidemic Agents / Q000494:pharmacology*; D008099:Liver / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology; D008103:Liver Cirrhosis / Q000201:enzymology / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D008297:Male; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D052250:Nitric Oxide Synthase Type III / Q000235:genetics / Q000378:metabolism*; D065626:Non-alcoholic Fatty Liver Disease; D051381:Rats; D017208:Rats, Wistar; D019821:Simvastatin / Q000494:pharmacology*; D053773:Transforming Growth Factor beta1 / Q000494:pharmacology
chemical_list: D000199:Actins; D024042:Collagen Type I; D004791:Enzyme Inhibitors; D000960:Hypolipidemic Agents; D019331:NG-Nitroarginine Methyl Ester; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; D019821:Simvastatin; D053773:Transforming Growth Factor beta1; C498862:Acta2 protein, rat; C496318:Nos2 protein, rat; C496316:Nos3 protein, rat